1. Field of the Invention
The present invention relates to a control system for ignition timing and exhaust gas recirculation of a combustion engine, and more particularly to a control system including a vacuum controller which is operated by a power source of negative pressure of a passageway of a carburetor to advance the ignition timing, and a controller having an EGR valve (exhaust gas recirculation valve) which is operated by a power source of the negative pressure to recirculate the exhaust gas into the intake manifold of the engine.
2. Description of the Prior Art
The conventional control system of this kind independently controls the vacuum controller and the EGR valve from each other. While the control system controls both of the ignition timing and the exhaust gas recirculation according to common information of an engine temperature, both the ignition timing and exhaust gas recirculation are also controlled independently from each other. It is necessary to control the ignition timing according to the condition of the exhaust gas recirculation, because optimum ignition timing depends upon the condition of the exhaust gas recircuration. Accordingly, the conventional control system is unable to perform a precise control of the ignition timing as well as the exhaust gas recirculation.